复合材料层压板低速冲击响应与损伤参数关系研究

LOW-VELOCITY IMPACT RESPONSE OF COMPOSITE LAMINATE AND ITS RELATIONSHIP WITH DAMAGE PARAMETERS

论文针对复合材料标准冲击试样,用落锤试验手段研究了三种不同铺层层压板的低速冲击特性.分析了冲击响应接触力和能量的基本特性及变化规律,发现冲击能量相对于层压板阻抗水平的不同会导致接触力-时间曲线形状的差异.从冲击总能量、吸收能量和损伤耗散能量的角度阐释了能量和接触力与层压板分层损伤、凹坑变形的关系.发现损伤直接取决于吸收能量,与冲击总能量有较好的正相关关系.最大接触力是表征层压板损伤阻抗性能的一个门槛值.在一定能量条件下进行冲击,峰值接触力若达到层压板的接触力门槛值,则峰值接触力不再随损伤程度而增加,不能继续作为损伤的表征参数.同时,进行了冲击过程动态有限元模拟,得到的冲击响应参数曲线和损伤结果与试验结果有较好的对应关系.

Three composite laminates with different layups are tested under low-velocity impact via dropping weight method. Their impact responses are recorded and some important parameters like contact forces and energies are analyzed. Based on these, impact energy, absorbed energy and damage dissipated energy are obtained, and their relationships with dent and delamination are also discussed in detail. Results show that. （1） contact force versus time curve apparently changes its shape while the energy level increases for the same damage resistant ability （2） damage evolution rests theoretically with the absorbed energy but is more closely relevant to the total impact energy （3）the maximum contact force is only a threshold, which is determined by the laminates resistant capability,and if the peak contact force reaches the threshold, a plateau emerges, thus can not be used to characterize the damage any longer. In addition, the software ABAQUS is employed to predict the impact response curves of composite laminates and damage evolution, showing good agreements with the experimental results.